Field of the Invention
This invention relates to a dynamic data visualization, and more particularly, to a graphic simulation of a fluid flow in a heterogeneous porous medium in hydrocarbon reservoirs on the basis of streamlines.
Description of the Related Art
Various methods for visualization of a flow of fluids between wells are known. In the conventional methods, all flows of the fluids are visualized on a graphic map in a form of various curves. Directions of flow are simulated directly along streamlines (See Sidelnikov K. A., Lyalin V. E., Grigoriev I. M. Simulation on the basis of tubes and streamlines methods/Bulletin of Udmurt University. Ser. Earth sciences. 2012. Edition 2. P. 109-119 and Bondarev A. E., Galaktionov V. A., Chechetkin V. M. Scientific visualization in the problems of computational mechanics of fluid and gas/Scientific electronic magazine “Scientific Visualization”, National Research Nuclear University “Moscow Engineering Physics Institute,” M., 2010, Volume 2, No. 4, P. 1-26).
A streamline is a curve, the tangent to which in each point coincides with the direction of motion velocity vector of fluid particles at this point. The streamlines are widely used in simulation of oil and gas reservoirs for waterflooding optimization, history matching and for visualization of results produced by a hydrodynamic simulator calculations.
In order to show the additional information at visualization, streamline color and thickness can be varied. A number of the streamlines to visualize flow of fixed fluid volume can vary also as follows: more streamlines can be considered for more accurate description. One of drawbacks of this approach is that it allows for visualization of the fluid flows only within one calculation step of hydrodynamic simulator and gives no accumulated indices. In other words, no information on how the fluid flows are changed during several calculation steps is available.
Thus, visualization using streamlines reflects only instantaneous indices. Considering the streamlines within one calculation step makes it impossible to determine zones covered by waterflooding for the entire period of a field development. Another drawback of this approach is that, when using the known method for data visualization at the fields with a large number of wells, a large number of streamlines on the map makes visual analysis of data almost impossible.
Reducing the number of streamlines by increasing a fluid volume visualized by one streamline results in loss of the information on hydrodynamic connectivity of wells having the fluid flow volume between them that is lowere than the volume referring to one streamline. There are visualization methods of direction of the fluid flow in heterogeneous porous medium using straight lines (See Thiele M R. Streamline simulation/8th International forum on reservoir simulation. Stresa/Lago Maggiore, Italy, 2005 and Batycky R. P., Thiele M. R. “System and methods for visual interpretation of well rate allocation factors”, U.S. Pat. No. 6,519,531). In this approach, an injection well and production well (between which the fluid is flowing) are connected by a straight line, the thickness of which corresponds to the fluid flow volume between the wells.
The advantage of this method is its applicability to the fields with a large number of wells. The data presented in this way can be analysed much more easily, moreover, this approach can be used to analyse fluid flows accumulated over several steps. The drawback of this approach is impossibility to define the actual fluid flow direction between the wells, which is necessary to determine the most waterflooded sectors of the reservoir. Since the medium wherein the fluid flow occurs is heterogeneous, usually the trajectory of particle motion between wells significantly differs from the straight line being visualized.
FIG. 1 illustrates a conventional method of construction of graphic model of fluid flow direction (130) in heterogeneous porous medium in hydrocarbon reservoirs based on streamlines between injection (120) and production wells (110) using streamlines.
Based on streamlines, the pairs of injection (120) and production wells (110) are determined, between which fluid flow (130) exists. Based on the data obtained on a set of wells, the graph is simulated on the map, and the vertices of the graph are wells (120 and 110) connected by an edge, if fluid flow (130) between them exists.
Patent application US 20120191432 (Khataniar et al.) describes the method of visualization using pie charts, where each sector corresponds to the well interacting with the given well, and the sector size corresponds to the fluid flow volume between the wells. The advantage of this approach is that it can be used to show the fluid flow volume between the wells accumulated over several calculation steps.
The drawback of this approach is that it has no graphic representation of main fluid flow directions between the wells that impedes significantly the acquisition of valid data for fluid flow adequate analysis.
Accordingly, an improved and efficient method for visualization of a fluid flow in a heterogeneous porous medium in hydrocarbon reservoirs on the basis of streamlines is desired.